Chromosome mapping of 28S ribosomal genes in 11 species of Cassidinae (Coleoptera: Chrysomelidae)

A cytogenetic analysis in two species of Cassidinae (Coleoptera, Chrysomelidae)

“…The high chromosome number, 2n = 30, of Anacassis fuscata , is in agreement with others found in the Neotropical tribe Mesomphaliini (= Stolaini), whose range in numbers goes from 2n = 22 to 2n(♂) = 51, in 24 checked species of six genera, where ten species of them had diploid numbers ≥ 30 chromosomes (De Julio et al 2010; Lopes et al 2016, 2017). Anacassis fuscata shows at least four acro/telocentric autosome pairs which points out to their possible origin from meta- or submetacentric autosomes by centric fissions, as it is found in other species of the tribe Mesomphaliini (De Julio et al 2010), and a tiny y-chromosome, but the X-chromosome was not distinguished.…”

“…Anacassis fuscata shows at least four acro/telocentric autosome pairs which points out to their possible origin from meta- or submetacentric autosomes by centric fissions, as it is found in other species of the tribe Mesomphaliini (De Julio et al 2010), and a tiny y-chromosome, but the X-chromosome was not distinguished. Nevertheless, Anacassis fuscata displays a simple sex-chromosome system Xy (probably Xy p ) in males, as occurs in species of other genera of this tribe, namely of Chelymorpha Chevrolat, 1837 , Cyrtonota Chevrolat, 1837, Mesomphalia Hope, 1839, Paraselenis Spaeth, 1913 and Stolas Billberg, 1820 (De Julio et al 2010; Lopes et al 2016, 2017), contrary to the highly complex sex-chromosome systems described in most species and chromosomal races of Botanochara , which are undoubtedly derived from the former simple one Xy p by chromosomal rearrangements (De Julio et al 2010; Lopes et al 2017). Thus, the tribe Mesomphaliini is strikingly apomorphous from cytogenetic grounds, both due to the high diploid chromosome numbers and the highly complex sex-chromosome systems of a fair number of its species.…”

“…The karyotype of Cassida humeralis has 2n = 18 chromosomes as in 23 (69.7%) of the 33 cytogenetically known species of the genus Cassida , and in 40 (65.6%) among the total of 61 checked species of the tribe Cassidini, including species of further fourteen genera (Petitpierre et al 1998; De Julio et al 2010; Lopes et al 2016, 2017). The prevalent metacentric shape of most autosomes in C. humeralis is also in agreement with those found in five other species of the same genus and in other genera of Cassidini tribe as well as a small metacentric X-chromosome and a tiny Y-chromosome (Petitpierre 1977; Petitpierre et al 1998; De Julio et al 2010).…”

“…The leaf beetles of subfamily Cassidinae are a very large group with some 6,000 species distributed in 43 tribes (Chaboo 2007). Nearly 130 species have been chromosomally analysed mostly from the Palaearctic, Neotropical and Oriental regions (Petitpierre et al 1988, Petitpierre et al 1998; De Julio et al 2010; Lopes et al 2015; Lopes et al 2017). Although the range of chromosome numbers is very large, from 2n = 12 to 2n (♂) = 51, roughly 40% of their species show 2n = 18 chromosomes (De Julio et al 2010).…”

Cytogenetic Analysis, Heterochromatin Characterization and Location of the rDNA Genes of Hycleus scutellatus (Coleoptera, Meloidae); A Species with an Unexpected High Number of rDNA Clusters

“…Although the use of satDNA as a phylogenetic marker is controversial, there are numerous examples in which the evolution of satDNA reflects species relationships in phylogenetic analyses [ 18 , 19 ]. Likewise, the molecular cytogenetic analysis of the nucleolar organizer regions (NORs) has been widely used in the study of chromosomal evolution and phylogeny among related species [ 20 , 21 ]. Traditionally, the chromosomal localization of the rDNA clusters has been performed using silver staining techniques.…”